The research project involves an assessment of the role of halogenated pyrimidine analogs in inducing neoplasia in Drosophila. Growth response to 5-bromodeoxyuridine treatment will be evaluated by tabulating the induction of supernumerary tissues and bristles on the adult wing, and BUdR-incorporated DNA will be examined by CsCl pycnography and pyrimidine isostich analysis. A biochemical analysis of analog-treated and normal cells will include an investigation into the nature and function of "perichromatin granules" isolated from nuclei. BIBLIOGRAPHIC REFERENCES: R. M. Rizki and T. M. Rizki. (1975) Morphogenic Effects of Halogenated Thymidine Analogues on Drosophila. VI. Causal Analysis of Bromodeoxyuridine-Induced Growth Lesions. DIFFERENTIATION 3, 133-142. R. M. Rizki, T. M. Rizki, and C. A. Andrews. (1975) Drosophila Cell Fusion Induced by Wheat Germ Agglutinin. JOURNAL OF CELL SCIENCE 18, 113-121.